ほとんど（〜ない）

About

ほとんど is an adverb/noun that means "mostly; basically; the majority".

E.g. みかんとオレンジはほとんど同おなじです。 "Mandarins and oranges are practically the same."

E.g. 宿題しゅくだいはほとんど終おわった。 "I've mostly finished my homework."

The ほとんど～ない pattern can be used to express that there is "hardly any of X", or that "X barely happens".

E.g. おかずをほとんど食たべていないのに、お菓子かしを食たべるのは良よくない。 "It's not good to eat candy when you've barely eaten your side dishes."

E.g. 昨日きのうはほとんど寝ねていません。 "I hardly slept yesterday."

ほとんど～ない may be used to express quantities, while めったに～ない can only describe actions.

ほとんど may be used without being paired with a negative verb, while めったに may not.

Summary

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  ほとんど is an adverb/noun that means "mostly; basically; the majority"

• 

  The ほとんど～ない pattern can be used to express that there is "hardly any of X", or that "X barely happens"